The surface loss of a material due to frictional forces.
The resistance of a material to loss of surface particles due to frictional forces.
Increase the speed of vulcanization, and in many instances, also improve the final product's physical properties.
These activators work with accelerators to reduce vulcanization time and improve a compound's final characteristics.
Materials such as antioxidants and anti-ozonants that serve to slow down the deterioration of rubber products that can occur as a result of exposure to light, heat, oxygen, radiation, ozone, etc.
A cavity or sac that deforms the surface of the material.
Any substance that alone, or in combination with other substances, is capable of producing a cellular structure in a plastic or rubber. Blowing agents include compressed gases that expand when pressure is released, soluble solids that leave pores when leached out, liquids that develop cells when they change to gases, and chemical agents that decompose or react under the influence of heat to form a gas. Chemical blowing agents range from simple salts such as ammonium or sodium bicarbonate to complex nitrogen releasing agents.
A generic term for materials containing many cells (either open, closed or both) dispersed throughout the mass.
Also known as Sponge Rubbers - it is a cellular material made of rubber. Cellular rubber products all contain cells or small hollow receptacles. The cells may either be open or interconnecting, or closed and not interconnecting.
A cell totally enclosed by its walls and hence not interconnecting with other cells.
The process of extruding two or more materials through a single die with two or more cavities arranged so that the extrudates merge and weld together into one structure.
Inadvertent densification of a cellular material during its manufacture resulting from breakdown of cellular structure.
An intimate mixture of a polymer with all the ingredients necessary for the finished article.
The PSI required to compress a lab slab a specified percentage of overall height, normally 25 percent.
A method of molding in which the rubber compound is molded between two plates that fit together to form the mold cavity. A molding press is used to provide the necessary force to close the mold.
The residual deformation after removal of the force that has subjected the specimen to compression.
A surface effect on rubber articles characterized by many minute cracks.
The act of vulcanization. See vulcanization.
An instrument for measuring the hardness of vulcanized rubber or plastic. Shore 00 scale is for sponge, Shore A dense/solid.
An arbitrary numbering scale that indicates the resistance to indentor point of the durometer. High values indicate harder materials.
An elastic rubber-like substance, such as natural or synthetic rubber.
Cellular rubber having closed cells made from a solid rubber compound.
Surplus material that is forced into crevices between mating mold surfaces during a molding operation and remains attached to the molded article at the parting line of a mold or die, or is extruded from a closed mold.
A molding process in that the mold halves begin the process clamped together. Once the mold is clamped, preheated rubber is forced into the sprue of a hot mold.
A cell not totally enclosed by its walls and hence interconnecting with other cells.
The surface cracks, checks or crazing caused by exposure to an atmosphere containing ozone.
A partially completed part that will be subjected to subsequent forming operations.
Pressure Sensitive Adhesive
Adhesive, which in dry form, is aggressively and permanently tacky at room temperature and firmly adheres to substrates upon contact without activation by water, solvent or heat.
A measure of the resilience, usually as the percentage of vertical return of an object that has fallen and bounced.
Also known as caoutchouc. It is a material that is capable of recovering from large deformations quickly and forcibly, and can be, or already is, modified to a state in which it is essentially insoluble (but can swell) in boiling solvent, such as benzene, methyl ethyl ketone and thanol-tulene aseotrope.
Strain remaining after complete release of the load producing the deformation.
The time an unvulcanized rubber stock can be stored without losing any of its processing or curing properties.
See durometer hardness.
A relatively dense layer at the surface of a cellular material.
Cellular rubber consisting predominantly of open cells made from a solid rubber compound.
In an injection or transfer mold, the main feed channel that connects the mold-filling orifice with the runners leading to each cavity gate.
A material upon the surface of which an adhesive is applied for any purpose such as bonding or coating.
The resistance to growth of a nick or cut when tension is applied to the test specimen, commonly expressed as pounds per inch or newtons per meter.
The maximum tensile stress applied during stretching a specimen to rupture.
A molding process where a rubber preform is heated and forced by a plunger through a funnel-shaped opening, or sprue, into the mold cavity. Often considered a form of compression molding.
Preferably used to denote the product of vulcanization, without reference to its shape or form.
An irreversible process during which a rubber compound, through a change in its chemical structure (i.e., cross-linking), becomes less plastic and more resistant to swelling by organic liquids, and elastic properties are conferred, improved or extended over a greater range of temperature.
The addition of vulcanizing agents to a compound's composition affecting its physical properties. They must be stable, free from bloom and possess the required building tack; all of which is dependent on the compounding and processing.
The surface deterioration of a rubber article during outdoor exposure, such as checking, cracking, crazing or chalking.